# CQLSh: the CQL shell cqlsh is a command line shell for interacting with ScyllaDB through CQL (the Cassandra Query Language). It is shipped with every ScyllaDB package and can be found in the `bin/` directory. In addition, it is available on [Docker Hub](https://hub.docker.com/r/scylladb/scylla-cqlsh) and in the [Python Package Index (PyPI)](https://pypi.org/project/scylla-cqlsh/). cqlsh utilizes the Python native protocol driver and connects to the single node specified on the command line. See the [scylla-cqlsh](https://github.com/scylladb/scylla-cqlsh) repository on GitHub for usage examples. ## Compatibility cqlsh is compatible with Python 3.8 - Python 3.11. A given version of cqlsh is only guaranteed to work with the version of ScyllaDB that it was released with. cqlsh may work with older or newer versions of ScyllaDB without any guarantees. ## Optional Dependencies cqlsh ships with all essential dependencies. However, there are some optional dependencies that can be installed to improve the capabilities of cqlsh. ### pytz By default, cqlsh displays all timestamps with a UTC timezone. To support display of timestamps with another timezone, the [pytz](http://pytz.sourceforge.net/) library must be installed. See the `timezone` option in [cqlshrc]() for specifying a timezone to use. ### cython The performance of cqlsh’s `COPY` operations can be improved by installing [cython](http://cython.org/). This will compile the python modules that are central to the performance of `COPY`. ## cqlshrc The `cqlshrc` file holds configuration options for cqlsh. By default, this is in the user’s home directory: `~/.cassandra/cqlsh`, but a custom location can be specified with the `--cqlshrc` option. Example config values and documentation can be found in the `conf/cqlshrc.sample` file of a tarball installation. You can also view the latest version of [cqlshrc online](https://github.com/scylladb/scylla-cqlsh/blob/master/conf/cqlshrc.sample). ## Command Line Options Usage: `cqlsh [options] [host [port]]` Options: `-C` `--color` : Force color output `--no-color` : Disable color output `--browser` : Specify the browser to use for displaying cqlsh help. This can be one of the [supported browser names](https://docs.python.org/2/library/webbrowser.html) (e.g. `firefox`) or a browser path followed by `%s` (e.g. `/usr/bin/google-chrome-stable %s`). `--ssl` : Use SSL when connecting to ScyllaDB. `-u` `--user` : Username to authenticate against ScyllaDB. `-p` `--password` : The password to authenticate against ScyllaDB, which should be used in conjunction with `--user` `-k` `--keyspace` : Keyspace to authenticate to should be used in conjunction with `--user` `-f` `--file` : Execute commands from the given file, then exit `--debug` : Print additional debugging information `--encoding` : Specify a non-default encoding for output (defaults to UTF-8) `--cqlshrc` : Specify a non-default location for the `cqlshrc` file `-e` `--execute` : Execute the given statement, then exit `--connect-timeout` : Specify the connection timeout in seconds (defaults to 2s) `--request-timeout` : Specify the request timeout in seconds (defaults to 10s) `-t` `--tty` : Force tty mode (command prompt) ## Special Commands In addition to supporting regular CQL statements, cqlsh also supports a number of special commands that are not part of CQL. These are detailed below. ### CONSISTENCY Usage: `CONSISTENCY ` Sets the consistency level for operations to follow. Valid arguments include: ```cql - ANY - ONE - TWO - THREE - QUORUM - ALL - LOCAL_QUORUM - LOCAL_ONE - SERIAL - LOCAL_SERIAL ``` ### SERIAL CONSISTENCY Usage: `SERIAL CONSISTENCY ` Sets the serial consistency level for operations to follow. Valid arguments include: - `SERIAL` - `LOCAL_SERIAL` The serial consistency level is only used by conditional updates (`INSERT`, `UPDATE`, and `DELETE` with an `IF` condition). For those, the serial consistency level defines the consistency level of the serial phase (or “paxos” phase) while the normal consistency level defines the consistency for the “learn” phase, i.e. what type of reads will be guaranteed to see the update right away. For example, if a conditional write has a consistency level of `QUORUM` (and is successful), then a `QUORUM` read is guaranteed to see that write. However, if the regular consistency level of that write is `ANY`, then only a read with a consistency level of `SERIAL` is guaranteed to see it (even a read with consistency `ALL` is not guaranteed to be enough). ### SHOW VERSION This command is useful if you want to check which Cassandra version is compatible with your ScyllaDB version. Note that the two standards are not 100% identical and this command is simply a comparison tool. If you want to display your current ScyllaDB version, refer to [Check your current version of ScyllaDB](https://docs.scylladb.com/manual/master/operating-scylla/admin.md#check-your-current-version-of-scylla). The display shows: * The cqlsh tool version that you’re using * The Apache Cassandra version that your version of ScyllaDB is most compatible with * The CQL protocol standard that your version of ScyllaDB is most compatible with * The native protocol standard that your version of ScyllaDB is most compatible with Example: ```none cqlsh> SHOW VERSION ``` Returns: ```none [cqlsh 5.0.1 | Cassandra 3.0.8 | CQL spec 3.3.1 | Native protocol v4] ``` ### SHOW HOST Prints the IP address and port of the ScyllaDB node that cqlsh is connected to in addition to the cluster name. Example: ```none cqlsh> SHOW HOST ``` Returns: ```none Connected to Prod_Cluster at 192.0.0.1:9042. ``` ### SHOW SESSION Pretty prints a specific tracing session. Usage: `SHOW SESSION ` Example usage: ```none cqlsh> SHOW SESSION 95ac6470-327e-11e6-beca-dfb660d92ad8 ``` Returns: ```none Tracing session: 95ac6470-327e-11e6-beca-dfb660d92ad8 activity | timestamp | source | source_elapsed | client -----------------------------------------------------------+----------------------------+-----------+----------------+----------- Execute CQL3 query | 2016-06-14 17:23:13.979000 | 127.0.0.1 | 0 | 127.0.0.1 Parsing SELECT * FROM system.local; [SharedPool-Worker-1] | 2016-06-14 17:23:13.982000 | 127.0.0.1 | 3843 | 127.0.0.1 ... ``` ### SOURCE Reads the contents of a file and executes each line as a CQL statement or special cqlsh command. Usage: `SOURCE ` Example usage: ```none cqlsh> SOURCE '/home/thobbs/commands.cql' ``` ### CAPTURE Begins capturing command output and appending it to a specified file. Output will not be shown at the console while it is captured. Usage: ```none CAPTURE ''; CAPTURE OFF; CAPTURE; ``` That is, the path to the file to be appended to must be given inside a string literal. The path is interpreted relative to the current working directory. The tilde shorthand notation (`'~/mydir'`) is supported for referring to `$HOME`. Only query result output is captured. Errors and output from cqlsh-only commands will still be shown in the cqlsh session. To stop capturing output and show it in the cqlsh session again, use `CAPTURE OFF`. To inspect the current capture configuration, use `CAPTURE` with no arguments. ### HELP Gives information about cqlsh commands. To see available topics, enter `HELP` without any arguments. To see help on a topic, use `HELP `. Also, see the `--browser` argument for controlling what browser is used to display help. ### TRACING Enables or disables tracing for queries. When tracing is enabled, once a query completes, a trace of the events during the query will be printed. Usage: ```none TRACING ON TRACING OFF ``` ### PAGING Enables paging, disables paging, or sets the page size for read queries. When paging is enabled, only one page of data will be fetched at a time, and a prompt will appear to fetch the next page. Generally, it’s a good idea to leave paging enabled in an interactive session to avoid fetching and printing large amounts of data at once. Usage: ```none PAGING ON PAGING OFF PAGING ``` ### EXPAND Enables or disables vertical printing of rows. Enabling `EXPAND` is useful when many columns are fetched, or the contents of a single column are large. Usage: ```none EXPAND ON EXPAND OFF ``` ### LOGIN Authenticate as a specified ScyllaDB user for the current session. Usage: ```none LOGIN [] ``` ### EXIT Ends the current session and terminates the cqlsh process. Usage: ```none EXIT QUIT ``` ### CLEAR Clears the console. Usage: ```none CLEAR CLS ``` ### DESCRIBE Prints a description (typically a series of DDL statements) of a schema element or the cluster. This is useful for dumping all or portions of the schema. ```cql DESCRIBE CLUSTER DESCRIBE SCHEMA DESCRIBE KEYSPACES DESCRIBE KEYSPACE DESCRIBE TABLES DESCRIBE TABLE DESCRIBE MATERIALIZED VIEW DESCRIBE TYPES DESCRIBE TYPE DESCRIBE FUNCTIONS DESCRIBE FUNCTION DESCRIBE AGGREGATES DESCRIBE AGGREGATE ``` In any of the commands, `DESC` may be used in place of `DESCRIBE`. You may also omit what you want to describe and just simply use `DESCRIBE `. This will look for the object : in a specific order: keyspace, table, view, index, user-defined type, user-defined function, user-defined aggregate. The `DESCRIBE CLUSTER` command prints the cluster name and partitioner: ```none cqlsh> DESCRIBE CLUSTER Cluster: Test Cluster Partitioner: Murmur3Partitioner ``` The `DESCRIBE SCHEMA` command prints the DDL statements needed to recreate the entire schema. The higher tiers of the statement can also include information that can be used to restore authentication/authorization and service levels. This is especially useful for cloning a cluster or restoring its state from a backup. See [a dedicated article](https://docs.scylladb.com/manual/master/cql/describe-schema.md) to learn more. ### COPY TO Copies data from a table to a CSV file. ```cql COPY [(, ...)] TO WITH [AND ...] ``` If no columns are specified, all columns from the table will be copied to the CSV file. A subset of columns to copy may be specified by adding a comma-separated list of column names surrounded by parenthesis after the table name. The `` should be a string literal (with single quotes) representing a path to the destination file. The file name can also contain the special value `STDOUT` (without single quotes) print the CSV to STDOUT. See [Shared COPY Options](#shared-copy-options) for options that apply to both `COPY TO` and `COPY FROM`. #### Options for COPY TO `MAXREQUESTS` : The maximum number token ranges to fetch simultaneously. Defaults to 6. `PAGESIZE` : The number of rows to fetch in a single page. Defaults to 1000. `PAGETIMEOUT` : By default, the page timeout is 10 seconds per 1000 entries in the page size or 10 seconds if pagesize is smaller. `BEGINTOKEN`, `ENDTOKEN` : Token range to export. Defaults to exporting the full ring. `MAXOUTPUTSIZE` : The maximum size of the output file measured in number of lines; beyond this maximum the output file will be split into segments. -1 means unlimited, and is the default. `ENCODING` : The encoding used for characters. Defaults to `utf8`. ### COPY FROM Copies data from a CSV file to table. ```cql COPY [(, ...)] FROM WITH [AND ...] ``` If no columns are specified, all columns from the CSV file will be copied to the table. A subset of columns to copy may be specified by adding a comma-separated list of column names surrounded by parenthesis after the table name. The `` should be a string literal (with single quotes) representing a path to the source file. The file name can also contain the special value\`\`STDIN\`\` (without single quotes) to read the CSV data from STDIN. See [Shared COPY Options](#shared-copy-options) for options that apply to both `COPY TO` and `COPY FROM`. #### Options for COPY FROM `INGESTRATE` : The maximum number of rows to process per second. Defaults to 100000. `MAXROWS` : The maximum number of rows to import. -1 means unlimited, and is the default. `SKIPROWS` : A number of initial rows to skip. Defaults to 0. `SKIPCOLS` : A comma-separated list of column names to ignore. By default, no columns are skipped. `MAXPARSEERRORS` : The maximum global number of parsing errors to ignore. -1 means unlimited, and is the default. `MAXINSERTERRORS` : The maximum global number of insert errors to ignore. -1 means unlimited. The default is 1000. `ERRFILE` = : A file to store all rows that could not be imported. By default, this is `import__.err` where `` is your keyspace and `` is your table name. `MAXBATCHSIZE` : The max number of rows inserted in a single batch. Defaults to 20. `MINBATCHSIZE` : The min number of rows inserted in a single batch. Defaults to 2. `CHUNKSIZE` : The number of rows that are passed to child worker processes from the main process at a time. Defaults to 1000. #### Shared COPY Options Options that are common to both `COPY TO` and `COPY FROM`. `NULLVAL` : The string placeholder for null values. Defaults to `null`. `HEADER` : For `COPY TO`, controls whether the first line in the CSV output file will contain the column names. For COPY FROM, specifies whether the first line in the CSV input file contains column names. Defaults to `false`. `DECIMALSEP` : The character that is used as the decimal point separator. Defaults to `.`. `THOUSANDSSEP` : The character that is used to separate thousands. Defaults to the empty string. `BOOLSTYlE` : The string literal format for boolean values. By default this is `True, False`. `NUMPROCESSES` : The number of child worker processes to create for `COPY` tasks. Defaults to a max of 4 for `COPY FROM` and 16 for `COPY TO`. However, at most (num_cores - 1), processes will be created. `MAXATTEMPTS` : The maximum number of failed attempts to fetch a range of data (when using `COPY TO`) or insert a chunk of data (when using `COPY FROM`) before giving up. Defaults to 5. `REPORTFREQUENCY` : How often status updates are refreshed in seconds. By default, this is 0.25 seconds. `RATEFILE` : An optional file to export rate statistics to. By default, this is disabled and statistics are not exported to a file. See also: CQLSH [lesson](https://university.scylladb.com/courses/data-modeling/lessons/basic-data-modeling-2/topic/cql-cqlsh-and-basic-cql-syntax/) on ScyllaDB University * [Apache Cassandra Query Language (CQL) Reference](https://docs.scylladb.com/manual/master/cql/index.md) [Back](https://docs.scylladb.com/manual/master/getting-started/index.md) Copyright © 2016, The Apache Software Foundation. Apache®, Apache Cassandra®, Cassandra®, the Apache feather logo and the Apache Cassandra® Eye logo are either registered trademarks or trademarks of the Apache Software Foundation in the United States and/or other countries. No endorsement by The Apache Software Foundation is implied by the use of these marks.